Fast synthesis of nanostructured microspheres of a bridged silsesquioxane via ultrasound-assisted sol-gel processing

HERNÁN E. ROMEO; MARÍA A. FANOVICH; ROBERTO J. J. WILLIAMS; LIBOR MATEJKA; JOSEF PLESTIL; JIRÍ BRUS

MACROMOLECULAR CHEMISTRY AND PHYSICS

Wiley-VCH

Lugar: Weinheim, Alemania ; Año: 2009 p. 172 - 178

1022-1352

Microspheres of a nanostructured bridged silsesquioxane were synthesized by employing ultrasound-assisted self-assembly of a bridged monomer via sol-gel processing. The bridged precursor was synthesized from glycidoxypropyl(trimethoxysilane) (2 mol) and cyclohexylamine (1 mol). The main factor controlling the generation of a stable dispersion of microspheres was the time at which phase separation of the silsesquioxane was produced during the hydrolytic condensation. An appropriate blend of THF/n-hexane as solvent enabled to rapidly generate a stable dispersion exhibiting a low polydispersity. The mild reaction conditions produced the nanostructuring of the silsesquioxane characterized by a fine structure in SAXS spectrum. Inorganic domains were arranged in a two-dimensional hexagonal system leading to the formation of cavities in the microspheres which could be employed as host-guest systems in advanced technologies.